Percutaneous ultrasound-guided renal biopsies in a paediatric population: comparison of coaxial and non-coaxial techniques using 18-gauge core biopsy needles.

BACKGROUND

Percutaneous ultrasound-guided biopsy is performed in paediatric patients for evaluation of diffuse renal parenchymal disease. When compared with the non-coaxial technique, the coaxial technique has the advantages of obtaining multiple tissue cores via a single capsular puncture and post-biopsy tract embolisation.

OBJECTIVES

To compare the coaxial and non-coaxial techniques of percutaneous ultrasound (US)-guided biopsy of native kidney parenchyma in children and adolescents with renal disease.

MATERIALS AND METHODS

We retrospectively identified consecutive patients who underwent percutaneous US-guided renal biopsy using an 18-gauge core biopsy needle from July 2019 to July 2021 in a single tertiary paediatric nephrology centre. Focal renal tumour biopsy and transplant kidney biopsy were excluded. The total glomerular yield, specimen adequacy, complication rate and procedural time between the coaxial and non-coaxial groups were compared.

RESULTS

There were 34 percutaneous US-guided renal biopsies: 22 using a coaxial technique and 12 using a non-coaxial technique. The total median glomerular yield obtained was higher in the coaxial group (coaxial=37.9; non-coaxial=22.2; P=0.02). No statistically significant difference was noted between specimen adequacy (coaxial=100%; non-coaxial=91.7%; P=0.35). While no statistically significant difference was detected for overall complication rates (coaxial=13.6%; non-coaxial=41.7%; P=0.09), the coaxial group had a lower rate of haemorrhagic complications (coaxial=4.5%; non-coaxial=41.7%; P=0.01). One patient in the non-coaxial group had post-biopsy haemorrhage requiring embolisation. The procedural time was shorter in the coaxial group (coaxial=26.3 ± 7.0 min; non-coaxial=51.3 ± 11.5 min; P<0.001).

CONCLUSION

Percutaneous US-guided renal biopsy in children using the coaxial technique has significantly higher total glomerular yield, shorter procedural time and fewer haemorrhagic complications, compared to biopsies using the non-coaxial technique.